Hi,
I am looking for a method to get column13 to column 50 data from the 1st line of a multiline reord. The records are stored in a large file and are separated by newline. sample format is
(data in red is to be extracted)
<header>
A001dfhskhfkdsh hajfhksdhfjh... (3 Replies)
I'm working on formatting some attendance data to meet a vendors requirements to upload to their system. With some help on the forums here, I have the data close. But they've since changed what they want.
The vendor wants me to submit three fields to them. Field 1 is the studentid field,... (4 Replies)
hi all,
when i try to start an applicationserver
for an example:
./kStart.sh > out.txt
so kStart.sh script will start the application server and write the details to out.txt
but in mycase... it is writing to out.txt and as well it is showing in the prompt also...
I want only the... (2 Replies)
Hi,
I have data in following format.
10001, John, Daves, Architecture, -2219
10002, Jim, Cirners, Businessman, -2219
1003, Tom, Katch, Engineer, -14003
I want to select the last column of the above given file and paste it on a different file in the following manner.
File TEST column... (11 Replies)
The script must ask the user to enter the user name and check whether the user exists in /etc/passwd (you must allow the partial usernames also). If the username exists, display the details as:
List of users
Login Name:
User ID:
... (3 Replies)
Hi Friends,
I'm a great fan of this forum... it has helped me tone my skills in shell scripting. I have a challenge here, which I'm sure you guys would help me in achieving...
File A has a list of job ids and I need to compare this with the File B (*.log) and File C (extend *.log) and copy... (6 Replies)
I have a flatfile A.txt
date|products|notes|location
121117|a108|this is a test|florida
121118|b111|just test it|tampa
How do i write an awk to create a file name as location.txt and have products:notes
awk -F'|' '{ print $2 ":" $3 }' A.txt > $4.txt
I am sure it cannot write to... (5 Replies)
Trying to use perl to output specific fields from all text files in a directory to one new file. Each text file on a new line. The below seems to work for one text file but not more. Thank you :).
perl -ne 's/^#//; @n = (6, 7, 8, 16); print if $. ~~ @n' *.txt > out.txt
format of all text... (2 Replies)
I'm a complete beginner in UNIX (and not a computer science student either), just undergoing a tutoring course. Trying to replicate the instructions on my own I directed output of the ls listing command (lists all files of my home directory ) to My_dir.tsv file (see the screenshot) to make use of... (9 Replies)
Discussion started by: scrutinizerix
9 Replies
LEARN ABOUT OSX
pipe
PIPE(2) BSD System Calls Manual PIPE(2)NAME
pipe -- create descriptor pair for interprocess communication
SYNOPSIS
#include <unistd.h>
int
pipe(int fildes[2]);
DESCRIPTION
The pipe() function creates a pipe (an object that allows unidirectional data flow) and allocates a pair of file descriptors. The first
descriptor connects to the read end of the pipe; the second connects to the write end.
Data written to fildes[1] appears on (i.e., can be read from) fildes[0]. This allows the output of one program to be sent to another pro-
gram: the source's standard output is set up to be the write end of the pipe; the sink's standard input is set up to be the read end of the
pipe. The pipe itself persists until all of its associated descriptors are closed.
A pipe whose read or write end has been closed is considered widowed. Writing on such a pipe causes the writing process to receive a SIGPIPE
signal. Widowing a pipe is the only way to deliver end-of-file to a reader: after the reader consumes any buffered data, reading a widowed
pipe returns a zero count.
The generation of the SIGPIPE signal can be suppressed using the F_SETNOSIGPIPE fcntl command.
RETURN VALUES
On successful creation of the pipe, zero is returned. Otherwise, a value of -1 is returned and the variable errno set to indicate the error.
ERRORS
The pipe() call will fail if:
[EFAULT] The fildes buffer is in an invalid area of the process's address space.
[EMFILE] Too many descriptors are active.
[ENFILE] The system file table is full.
SEE ALSO sh(1), fork(2), read(2), socketpair(2), fcntl(2), write(2)HISTORY
A pipe() function call appeared in Version 6 AT&T UNIX.
4th Berkeley Distribution February 17, 2011 4th Berkeley Distribution